CC8 Nondestructive Testing (NDT)

NDT Profile Measurements

Prior to the CC8 Trafficking for Phases 1 through Phase 4, baseline Non-Destructive Testing (NDT) was performed. The objective of obtaining the baseline NDT was to collect Heavy-Weight Deflectometer (HWD) and Portable Seismic Properties Analyzer (PSPA) data, which could be used for backcalculation of pavement layer modulus values, and for monitoring slab curling and changing support conditions. In additional to HWD and PSPA, a series of testing was performed using the NDT equipment described below.

In addition to baseline NDT data, a baseline visual condition survey was performed on the concrete surface in accordance to ASTM D5340. Throughout the duration of CC8 testing distress surveys were performed on a daily basis. Visual inspection was performed immediately following trafficking using a combination of chalk marks, flashlights, and other tools to help locate very fine cracks. To read more on the pavement distress surveys click here.

All tests performed prior to trafficking were repeated at the end of trafficking at the same locations for comparison. For more information on NDT Test Plan for each Phase of CC8 click on the links below:

2D/3D Imaging using the WayLink Imaging System in the NDT Van as seen the figure below.2D and 3D image data was collected pre and post trafficking across the entirety of the CC8 Test Section from west to east.

Waylink Imaging System on NDT Van (Click to Zoom)

Mobile Profiling using the NDT Mobile Profiler illustrated in the figure below. Longitudinal profiles were collected pre and post trafficking at the same time as the 2D/3D Imaging.

Mobile Profiler on NDT Van (Click to Zoom)

Joint Groove Profiler measurements using the Joint Groove Profile illustrated below were collected on pre and post trafficking on slabs N3 and N4.

Joint Groove Profiler (Click to Zoom)

GPRmeasurements using a 900MHz GPR antenna (walk behind) and mobile Ground/Air Coupled GPR as seen in the figures below. Both GPR devices were used to collect measurements from east to west along CC8 pre and post trafficking. Ground/Air Coupled GPR measurements were collected in conjunction with the Imaging and Mobile Profiler.

Air/Ground Coupled GPR (Click to Zoom)

GPR Measurements using a 1500 MHz walk behind GPR as illustrated below. GPR measurements were collected to monitor construction thickness of each layer and to monitor layer thickness changes during the duration of testing.

Walk Behind GPR Cart (Click to Zoom)

PSPA. Portable Seismic Pavement Analyzer (PSPA) measurements were collected pre and post trafficking and on a weekly basis at the center of all the slabs on CC8. The PSPA device is illustrated below.

PSPA (Click to Zoom)

HWD testing was performed pre and post trafficking and on a weekly basis. The target loading sequence was: 4,000 lbs., 8,000 lbs., and 12,000 lbs. with an approximate 12,000-lb seating load. The deflection data was used for monitoring modulus changes using BAKFAA and the changing support conditions with increasing pass numbers. The HWD is illustrated below.

HWD (click to Zoom)

ELATextur measurements were collected pre and post trafficking to monitor abrasion on the concrete surface at both trafficked and non-trafficked areas. The ELATextur device is illustrated below.

ELATextur (Click to Zoom)

SurPro measurements were collected pre and post trafficking in the transverse direction across the full width of the CC8 pavement surface to monitor profile changes in the pavement as a result of trafficking. The SurPro device is illustrated below.

SurPro (Click to Zoom)

MIT Scan measurements were collected pre and post trafficking to verify the dowel bar placement at all of the joints in the CC8 test section. The MIT device can be seen below.

MIT Scan (Click to Zoom)

Throughout the duration of CC8 testing HWD and PSPA were collected on a weekly basis.

Pavement Distress Survey

Cumulative plots of crack mapping were prepared. On these plots, the distresses were color-coded to separate dates/passes of distress surveys on which the new distresses were observed. The observed cracks were then processed and analyzed as followed: linear cracks for each test item were measured and cumulatively added; and fatigue areas for each test item were measured and cumulatively added. SCI calculations for each Phase of CC8 were generated for each distress survey.

To be directed to the CC8 Phase 1 Overload Pavement Distress Map and Log, click here.

To be directed to the CC8 Phase 2 Overlay Pavement Distress Map, and Log click here.